Disc drives are well known which store digital information in a plurality of circular, concentric data tracks of a disc. Discs are mounted on a spindle motor which causes the discs to spin and the surfaces of the discs to pass under heads carried by an actuator block movably coupled relative to the discs for selective access to data tracks of the discs. Heads carry transducers which read and write information to the disc surface. The actuator block is controlled via electronic circuitry coupled to the actuator drive for positioning the actuator block for aligning heads relative to selected data tracks.
Disc data density is increasing such that it is important to more accurately position heads relative to data tracks for retrieving selected information. The actuator block is rotationally coupled to the disc drive by a bearing which allows the actuator block to rotate about a rotation axis to move the actuator block along an arcuate path. Off-axis movement of the actuator block relative to or transverse to the rotation axis affects accurate head placement.
Thus, it is desirable to provide a bearing with sufficient stability to limit off-axis movement of the actuator block for precision head placement relative to selected data tracks. The present invention addresses these and other problems, and offers other advantages over the prior art.